Amaterial used for electrical wiring must have b. high conductivity

If a material is going to be used for electrical wiring, it must have high conductivity. Electrical conductivity is the measure of a materials ability to allow the movement of an electric charge. Its SI is the Siemens per meter. Electrical conductivity is also known as specific conductance, a material with higher electrical conductivity would be the best preference for making electric wires. 

This is the answer: body 1 + engine 2

stands for electromotive force and it is measured in volts. despite its name, it is not actually the force in the sense of being a "pushing" or "pulling" (not measured in newtons).an equation that relates emf,  ℰ,  to a battery's terminal voltage, v, current, i, and internal resistance, r, is    ℰ = v + irin this case, the emf can be interpreted as a voltage—a difference in electric potential.i would not say that it would be considered an energy. if emf can be defined as the energy/work per a unit charge from a battery or other electric source, then it is not strictly energy.